Add 21/42 and 9/28
21/42 + 9/28 is 23/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
9/28 = 9 × 3/28 × 3 = 27/84 - Add the two like fractions:
42/84 + 27/84 = 42 + 27/84 = 69/84 - 69/84 simplified gives 23/28
- So, 21/42 + 9/28 = 23/28
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